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SSC JE Electrical 2019 with solution SET-1
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In the circuit shown, if R = 0, then the phase angle between v(t) and i(t) is

In the given circuit if R = 0 then the circuit becomes purely inductive. So the phase angle between v(t) and i(t) is 90°.

SSC JE Electrical 2019 with solution SET-1
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________ is used to manufacture stay wire, earth wire, and structural components

Galvanized steel conductors do not corrode, and possess high resistance. Hence such Wires are used in telecommunications circuits, earth wires, guard wire, stray wire, etc.

SSC JE Electrical 2019 with solution SET-1
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Which of the following is the correct relation regarding coupled coils?

Mutual inductance between two coupled coils is given by the relation

M = K√L1L2

Where

L1L2 = Inductance of the coil

K = Coefficient of coupling

When K = 1 coils are said to be tightly coupled and if K is a fraction the coils are said to be loosely coupled.

Here

Kmax =1

Kmin =0

∴ m ≤ (L1 L2 )0.5

SSC JE Electrical 2019 with solution SET-1
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Two bulbs of rating 230V, 60W, and 230V, 100W are connected in parallel across supply mains, Identify the correct statement

For Bulb 1

Power = 60 W

Voltage = 230 V

R = V2/P

R = (230 × 230)/60

R = 881.66 Ω

For Bulb 2

Power = 230 W

Voltage = 120 V

R = V2/P

R = (230 × 230)/100

R = 529 Ω

In a parallel connection, the voltage across each element is the same. So when a 60W bulb and 1o0 W bulb are connected in parallel, the voltage across them will be the same i.e 230 V in the given case. To find which bulb will glow brighter we need to find the power dissipation across each of them. From the relation

P = V2/R

Since the voltage is the same we can say that power dissipation will be higher for the bulb with lower resistance i.e. 100W bulb, or the bulb with the higher rating will glow brighter.

In a series connection, the current flowing across each element is the same. So when the 60W bulb and 100W bulb are connected in series, the same current will flow through them. To find which bulb will glow brighter we need to find the power dissipation across each of them. From the relation

P = I2R

SSC JE Electrical 2019 with solution SET-1
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_______ is the measuring unit of inductive susceptance

Susceptance is symbolized by the capital letter B. It is the reciprocal of AC reactance. Susceptance, like reactance, can be either capacitive or inductive. In the case of a magnetic field, the susceptance is inductive. In the case of an electric field, the susceptance is capacitive. Capacitive susceptance is symbolized BC and inductive susceptance is symbolized BL. In the case of a magnetic field, the susceptance is inductive. In the case of an electric field, the susceptance is capacitive. Inductive susceptance is assigned negative imaginary number values, and capacitive susceptance is assigned positive imaginary number values.

The formula for inductive susceptance is

BL =–1/2πfL

The unit of Inductive susceptance is Siemen or Mho.